HD/BR Uncompressed files?

[big_green_jelly_bean]

Are there any uncompressed files on Blue Ray or High Definition Disks? Im storing my HD/BR on a server, and am going to use system compression on these files.

Currently I compress
.XML
.BUP
.IFO

I want to do the same for the BR/HD images... I have saved 500mb so far with the above compressions...

Thanks